An anisotropic conductive adhesive (ACA) is a conductive adhesive that has electrical conductivity in one direction and almost no electrical conductivity or very high resistivity in the other directions. It has been widely used in the field of manufacturing display panels. Illustratively, the anisotropic conductive adhesive can be used for bonding an array substrate and a color filter substrate or for bonding pins.
In related art, there is an anisotropic conductive adhesive that includes a binder and conductive particles dispersed in the binder, wherein the conductive particle includes a resin sphere and a conductive layer formed on an outer surface of the resin sphere. When a first bonding surface and a second bonding surface are bonded with the anisotropic conductive adhesive, it is possible to first coat the anisotropic conductive adhesive on the first bonding surface and then to press the second bonding surface against the anisotropic conductive adhesive and apply pressure and heat thereto. In this way, the conductive particles dispersed in the anisotropic conductive adhesive will be in contact with each other under the pressure in a direction perpendicular to the first bonding surface, so that the two bonding surfaces have electrical conductivity in the direction perpendicular to the first bonding surface, but have very high resistivity or almost no electrical conductivity in the other directions.
In the process of carrying out the present disclosure, inventors found that the following problems exist in the related art: if the pressure applied to the anisotropic conductive adhesive is too small, the resistivity between the two bonding surfaces will be too large since the conductive particles are not in close contact with each other, and if the pressure is too large, a large number of conductive particles will be crushed, thereby resulting in an open circuit. Therefore, there is a high precision requirement for the pressure applied to the anisotropic conductive adhesive.